<?php
/*
 *  $Id: Mssql.php 7490 2010-03-29 19:53:27Z jwage $
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

/**
 * Doctrine_Connection_Mssql
 *
 * @package     Doctrine
 * @subpackage  Connection
 * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @author      Konsta Vesterinen <kvesteri@cc.hut.fi>
 * @author      Lukas Smith <smith@pooteeweet.org> (PEAR MDB2 library)
 * @version     $Revision: 7490 $
 * @link        www.doctrine-project.org
 * @since       1.0
 */
class Doctrine_Connection_Mssql extends Doctrine_Connection_Common
{
	/**
	 * @var string $driverName                  the name of this connection driver
	 */
	protected $driverName = 'Mssql';

	/**
	 * the constructor
	 *
	 * @param Doctrine_Manager $manager
	 * @param PDO $pdo                          database handle
	 */
	public function __construct(Doctrine_Manager $manager, $adapter)
	{
		// initialize all driver options
		$this->supported = array(
                          'sequences'             => 'emulated',
                          'indexes'               => true,
                          'affected_rows'         => true,
                          'transactions'          => true,
                          'summary_functions'     => true,
                          'order_by_text'         => true,
                          'current_id'            => 'emulated',
                          'limit_queries'         => 'emulated',
                          'LOBs'                  => true,
                          'replace'               => 'emulated',
                          'sub_selects'           => true,
                          'auto_increment'        => true,
                          'primary_key'           => true,
                          'result_introspection'  => true,
                          'prepared_statements'   => 'emulated',
		);

		parent::__construct($manager, $adapter);
	}

	/**
	 * quoteIdentifier
	 * Quote a string so it can be safely used as a table / column name
	 *
	 * Quoting style depends on which database driver is being used.
	 *
	 * @param string $identifier    identifier name to be quoted
	 * @param bool   $checkOption   check the 'quote_identifier' option
	 *
	 * @return string  quoted identifier string
	 */
	public function quoteIdentifier($identifier, $checkOption = false)
	{
		if ($checkOption && ! $this->getAttribute(Doctrine_Core::ATTR_QUOTE_IDENTIFIER)) {
			return $identifier;
		}

		if (strpos($identifier, '.') !== false) {
			$parts = explode('.', $identifier);
			$quotedParts = array();
			foreach ($parts as $p) {
				$quotedParts[] = $this->quoteIdentifier($p);
			}

			return implode('.', $quotedParts);
		}

		return '[' . str_replace(']', ']]', $identifier) . ']';
	}

	/**
	 * Adds an adapter-specific LIMIT clause to the SELECT statement.
	 * [ original code borrowed from Zend Framework ]
	 *
	 * License available at: http://framework.zend.com/license
	 *
	 * Copyright (c) 2005-2008, Zend Technologies USA, Inc.
	 * All rights reserved.
	 *
	 * Redistribution and use in source and binary forms, with or without modification,
	 * are permitted provided that the following conditions are met:
	 *
	 *     * Redistributions of source code must retain the above copyright notice,
	 *       this list of conditions and the following disclaimer.
	 *
	 *     * Redistributions in binary form must reproduce the above copyright notice,
	 *       this list of conditions and the following disclaimer in the documentation
	 *       and/or other materials provided with the distribution.
	 *
	 *     * Neither the name of Zend Technologies USA, Inc. nor the names of its
	 *       contributors may be used to endorse or promote products derived from this
	 *       software without specific prior written permission.
	 *
	 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
	 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
	 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
	 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
	 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
	 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	 *
	 * @param string $query
	 * @param mixed $limit
	 * @param mixed $offset
	 * @link http://lists.bestpractical.com/pipermail/rt-devel/2005-June/007339.html
	 * @return string
	 */
	public function modifyLimitQuery($query, $limit = false, $offset = false, $isManip = false, $isSubQuery = false)
	{
		if ($limit > 0) {
			$count = intval($limit);
			$offset = intval($offset);

			if ($offset < 0) {
				throw new Doctrine_Connection_Exception("LIMIT argument offset=$offset is not valid");
			}

			$orderby = stristr($query, 'ORDER BY');

			if ($orderby !== false) {
				// Ticket #1835: Fix for ORDER BY alias
				// Ticket #2050: Fix for multiple ORDER BY clause
				$order = str_ireplace('ORDER BY', '', $orderby);
				$orders = explode(',', $order);

				for ($i = 0; $i < count($orders); $i++) {
					$sorts[$i] = (stripos($orders[$i], ' desc') !== false) ? 'DESC' : 'ASC';
					$orders[$i] = trim(preg_replace('/\s+(ASC|DESC)$/i', '', $orders[$i]));

					// find alias in query string
					$helper_string = stristr($query, $orders[$i]);

					$from_clause_pos = strpos($helper_string, ' FROM ');
					$fields_string = substr($helper_string, 0, $from_clause_pos + 1);

					$field_array = explode(',', $fields_string);
					$field_array = array_shift($field_array);
					$aux2 = spliti(' as ', $field_array);
					$aux2 = explode('.', end($aux2));

					$aliases[$i] = trim(end($aux2));
				}
			}

			// Ticket #1259: Fix for limit-subquery in MSSQL
			$selectRegExp = 'SELECT\s+';
			$selectReplace = 'SELECT ';

			if (preg_match('/^SELECT(\s+)DISTINCT/i', $query)) {
				$selectRegExp .= 'DISTINCT\s+';
				$selectReplace .= 'DISTINCT ';
			}

			$fields_string = substr($query, strlen($selectReplace), strpos($query, ' FROM ') - strlen($selectReplace));
			$field_array = explode(',', $fields_string);
			$field_array = array_shift($field_array);
			$aux2 = spliti(' as ', $field_array);
			$aux2 = explode('.', end($aux2));
			$key_field = trim(end($aux2));

			$query = preg_replace('/^'.$selectRegExp.'/i', $selectReplace . 'TOP ' . ($count + $offset) . ' ', $query);

			if ($isSubQuery === true) {
				$query = 'SELECT TOP ' . $count . ' ' . $this->quoteIdentifier('inner_tbl') . '.' . $key_field . ' FROM (' . $query . ') AS ' . $this->quoteIdentifier('inner_tbl');
			} else {
				$query = 'SELECT * FROM (SELECT TOP ' . $count . ' * FROM (' . $query . ') AS ' . $this->quoteIdentifier('inner_tbl');
			}

			if ($orderby !== false) {
				$query .= ' ORDER BY ';

				for ($i = 0, $l = count($orders); $i < $l; $i++) {
					if ($i > 0) { // not first order clause
						$query .= ', ';
					}

					$query .= $this->quoteIdentifier('inner_tbl') . '.' . $aliases[$i] . ' ';
					$query .= (stripos($sorts[$i], 'asc') !== false) ? 'DESC' : 'ASC';
				}
			}

			if ($isSubQuery !== true) {
				$query .= ') AS ' . $this->quoteIdentifier('outer_tbl');

				if ($orderby !== false) {
					$query .= ' ORDER BY ';

					for ($i = 0, $l = count($orders); $i < $l; $i++) {
						if ($i > 0) { // not first order clause
							$query .= ', ';
						}

						$query .= $this->quoteIdentifier('outer_tbl') . '.' . $aliases[$i] . ' ' . $sorts[$i];
					}
				}
			}
		}

		return $query;
	}

	/**
	 * Creates dbms specific LIMIT/OFFSET SQL for the subqueries that are used in the
	 * context of the limit-subquery algorithm.
	 *
	 * @return string
	 */
	public function modifyLimitSubquery(Doctrine_Table $rootTable, $query, $limit = false, $offset = false, $isManip = false)
	{
		return $this->modifyLimitQuery($query, $limit, $offset, $isManip, true);
	}

	/**
	 * return version information about the server
	 *
	 * @param bool   $native  determines if the raw version string should be returned
	 * @return array    version information
	 */
	public function getServerVersion($native = false)
	{
		if ($this->serverInfo) {
			$serverInfo = $this->serverInfo;
		} else {
			$query      = 'SELECT @@VERSION';
			$serverInfo = $this->fetchOne($query);
		}
		// cache server_info
		$this->serverInfo = $serverInfo;
		if ( ! $native) {
			if (preg_match('/([0-9]+)\.([0-9]+)\.([0-9]+)/', $serverInfo, $tmp)) {
				$serverInfo = array(
                    'major' => $tmp[1],
                    'minor' => $tmp[2],
                    'patch' => $tmp[3],
                    'extra' => null,
                    'native' => $serverInfo,
				);
			} else {
				$serverInfo = array(
                    'major' => null,
                    'minor' => null,
                    'patch' => null,
                    'extra' => null,
                    'native' => $serverInfo,
				);
			}
		}
		return $serverInfo;
	}

	/**
	 * Checks if there's a sequence that exists.
	 *
	 * @param  string $seq_name     The sequence name to verify.
	 * @return boolean              The value if the table exists or not
	 */
	public function checkSequence($seqName)
	{
		$query = 'SELECT * FROM ' . $seqName;
		try {
			$this->exec($query);
		} catch(Doctrine_Connection_Exception $e) {
			if ($e->getPortableCode() == Doctrine_Core::ERR_NOSUCHTABLE) {
				return false;
			}

			throw $e;
		}
		return true;
	}

	/**
	 * execute
	 * @param string $query     sql query
	 * @param array $params     query parameters
	 *
	 * @return PDOStatement|Doctrine_Adapter_Statement
	 */
	public function execute($query, array $params = array())
	{
		if(! empty($params)) {
			$query = $this->replaceBoundParamsWithInlineValuesInQuery($query, $params);
		}

		return parent::execute($query, array());
	}

	/**
	 * execute
	 * @param string $query     sql query
	 * @param array $params     query parameters
	 *
	 * @return PDOStatement|Doctrine_Adapter_Statement
	 */
	public function exec($query, array $params = array())
	{
		if(! empty($params)) {
			$query = $this->replaceBoundParamsWithInlineValuesInQuery($query, $params);
		}

		return parent::exec($query, array());
	}

	/**
	 * Replaces bound parameters and their placeholders with explicit values.
	 *
	 * Workaround for http://bugs.php.net/36561
	 *
	 * @param string $query
	 * @param array $params
	 */
	protected function replaceBoundParamsWithInlineValuesInQuery($query, array $params) {

		foreach($params as $key => $value) {
			if(is_null($value)) {
				$value = 'NULL';
			}
			else {
				$value = $this->quote($value);
			}

			$re = '/([=,\(][^\\\']*)(\?)/iuU';

			$query = preg_replace($re, "\\1 {$value}", $query, 1);

		}

		return $query;

	}

	/**
	 * Inserts a table row with specified data.
	 *
	 * @param Doctrine_Table $table     The table to insert data into.
	 * @param array $values             An associative array containing column-value pairs.
	 *                                  Values can be strings or Doctrine_Expression instances.
	 * @return integer                  the number of affected rows. Boolean false if empty value array was given,
	 */
	public function insert(Doctrine_Table $table, array $fields)
	{
		$identifiers = $table->getIdentifierColumnNames();

		$settingNullIdentifier = false;
		$fields = array_change_key_case($fields);
		foreach($identifiers as $identifier) {
			$lcIdentifier = strtolower($identifier);

			if(array_key_exists($lcIdentifier, $fields)) {
				if(is_null($fields[$lcIdentifier])) {
					$settingNullIdentifier = true;
					unset($fields[$lcIdentifier]);
				}
			}
		}

		// MSSQL won't allow the setting of identifier columns to null, so insert a default record and then update it
		if ($settingNullIdentifier) {
			$count = $this->exec('INSERT INTO ' . $this->quoteIdentifier($table->getTableName()) . ' DEFAULT VALUES');

			if(! $count) {
				return $count;
			}

			$id = $this->lastInsertId($table->getTableName());

			return $this->update($table, $fields, array($id));
		}

		return parent::insert($table, $fields);
	}
}